package network;

import com.sun.xml.internal.ws.policy.privateutil.PolicyUtils;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Scanner;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class TcpEchoServer {
    private ServerSocket serverSocket = null;

    public TcpEchoServer(int port) throws IOException {
        serverSocket = new ServerSocket(port);
    }

    public void start() throws IOException {
        System.out.println("服务器启动！\n");

        while (true) {
            Socket clientSocket = serverSocket.accept();

            Thread t = new Thread(() -> {
                processConnection(clientSocket);
            });
            t.start();
        }
    }

    private void processConnection(Socket clientSocket) {
        System.out.printf("[%s:%d] 客户端上线！\n", clientSocket.getInetAddress().toString(), clientSocket.getPort());
        try (InputStream inputStream = clientSocket.getInputStream(); OutputStream outputStream = clientSocket.getOutputStream()) {
            while (true) {
                Scanner scanner = new Scanner(inputStream);

                if (!scanner.hasNext()) {
                    System.out.printf("[%s:%d] 客户端下线！\n", clientSocket.getInetAddress().toString(), clientSocket.getPort());
                    break;
                }

                String request = scanner.next();

                String response = process(request);

                PrintWriter printWriter = new PrintWriter(outputStream);
                printWriter.println(response);
                printWriter.flush();

                System.out.printf("[%s:%d] req: %s; resp: %s\n",clientSocket.getInetAddress().toString(), clientSocket.getPort(), request, response);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                clientSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public String process(String request) {
        return request;
    }

    public static void main(String[] args) throws IOException {
        TcpEchoServer server = new TcpEchoServer(10098);
        server.start();
    }
}
